Cloning and Analysis of Response to Stress of Elongation Factor 1β Gene from Angelica sinensis

Abstract:Elongation factor 1β (EF 1β) is one of the essential regulatory factors of peptide chain prolongation in the process of protein biosynthesis. This study cloned the EF 1β gene sequence from Angelica sinensis using homologous cloning and RACE amplification techniques. We analyzed the sequence characterization, protein structure characteristics and expression profiling of EF 1β gene under UV B radiation stress, to reveal the molecular mechanism of adaptation to UV B radiation stress in the process of cultivation habitat change of A. sinensis. The results showed that: (1) the full length sequence of EF 1β gene (950 bp), encodes 225 amino acids, which was named AsEF 1β gene (GenBank accession number: MG736314). The molecular weight of AsEF 1β is 24.5 kD, theoretical isoelectric point of 4.48. AsEF 1β belongs to hydrophilic amino acid, with the typical domain and conservative domain of family of EF 1B super protein, and has a guanine nucleotide exchange domain at its C terminal. The amino acid sequence of AsEF 1β gene showed the highest similarity with that of Daucus carota L. var. sativa Hoffm., which belongs to the same family of Umbrella. (2) the qRT PCR analysis results indicated that AsEF 1β gene in root of A. sinensis was significantly higher than that in stem and leaf (P<0.05). Under UV B radiation stress, the relative expression level of stem and leaf were up regulated, which was 2.43 times and 3.76 times that of natural light condition (P<0.05), respectively. Studies showed that AsEF 1β gene may be involved in the adaptation process of A. sinensis to UV B radiation stress, which will be laid for further exploration on its ecological regulations in the growth and development, formation of stress resistance and biosynthesis of pharmacodynamic substances of medicinal plants.